The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Torsion beams are used in a vehicle structure to attach the two rear wheels together through use of longitudinal control arms. A particular type of torsion beam often used on rear suspensions of front-wheel drive vehicles is a twist beam. Twist beam suspensions generally make use of a transverse strut interconnecting the longitudinal control arms. The transverse strut is rigid enough to prevent bending and flexible enough to allow torsion. Essentially, the beam can twist to reduce the effect of one wheel's motion on the other wheel. This dichotomy is accomplished by use of a tubular blank deformed into a member with tubular end sections and a U- or V-shaped transitional section. The cross-section is defined by an inner and outer skin layer connected by a bended contour.
Although a twist beam axle is less expensive and more compact than a fully independent suspension, it was not used in practice because of its short service life. High loads experienced by the transverse strut generally caused premature failure in intermediate areas between the end sections and the transitional section. The use of embossments between the end sections and the transitional section have somewhat counteracted this problem, but not to a satisfactory level. Additionally, the embossments create added scrap from cracks initiated during the forming operation because of the sharp radii required for manufacture.
Accordingly, it is desirable in the art to provide a product that does not suffer the above limitations. This, in turn, will provide a simple and durable twist beam axle for motor vehicles with an increased service life.